A comparative study of the fine structure of a variety of fish eyes will be made. Emphasis will be on cellular structure related to the economy of the aqueous humor and vitreous humor. Vitreous secretory cells will be sought in the falciform process and possible homologies between that organ and the vascular pecten of bird eye will be traced. Also, the vitreous will be examined for a possible cortical layer with hyalocytes. Although fish are presumed to have no ciliary processes, the tissues at the base of the iris will be examined for glandular cells that might be responsible for secretion of aqueous humor. Finally, although fish are presumed to have no canal of Schlemm, the so-called annular ligament will be studied for possible homology of structure and function of the trabecular angular meshwork and the canal of Schlemm.